Trends in osteoporotic hip fracture epidemiology over a 17-year period in a Spanish population: Alcorcón 1999-2015.

Our aim was to analyze trends in osteoporotic hip fracture rates in a suburban health area over a long time period. We detected a steady decrease, especially in women, that could be explained by historical, administrative, lifestyle changes as well as by medical behavior.

PURPOSE: The purpose of this study was to analyze trends in osteoporotic hip fracture rates in a suburban health area over a long time period.

METHODS: This is an ecological retrospective study of all discharges occurring in the Alcorcón health area and registered in the minimum basic data set (MBDS). The incidence of osteoporotic hip fracture was calculated by age and sex strata over the last 17 years. General lineal models were used to analyze trends.

RESULTS: Between 1999 and 2015, 4271 osteoporotic hip fractures occurred in people over 45 (78% women; mean age 83). The annual osteoporotic hip fracture rate was 290/100,000 persons over 45 (women 428; men 134), or 767/100,000 persons over 65 (women 1087, men 364). The incidence of fractures decreased yearly by 3.6% (95% CI 2.8 to 4.5) in the 1999-2015 period (p < 0.001) and was more pronounced in women [3.9% (95% CI 3.0 to 4.8)] than in men [2.4% (95% CI 0.9 to 3.8)]. In people over 65 years, fracture incidence decreased yearly by 3.7% (95% CI 2.8 to 4.6; p < 0.001). Again, this was more pronounced in women [4% (95% CI 3.05 to 4.9)] than in men [2.4 (95% CI 0.8 to 3.9)] while the female/male ratio decreased from 4.45 in 1999 to 2.4 in 2015. These differences were similar for extracapsular and intracapsular fractures.

CONCLUSIONS: These findings suggest a downward trend in the incidence of hip fracture in Alcorcón, both in men and in women. Possible explanations are discussed, including the effectiveness of osteoporosis diagnosis and treatment campaigns over the last 20 years, and the so-called "cohort effect."